Introducing the Experiment ZR012 by C3H5N3O9, with a Wankel rotary engine inspired design. A rotary engine runs smoother than a typical piston engine, with a linear power delivery similar to an electric motor. In the RX-8 for example, the motor can rev to a ridiculously high 8,500+ RPMs, without damaging the engine.

The trade-off for the refined, high-revving smoothness of rotary car engine – is that it does consume a significant amount of oil in comparison to a traditional car engine. It would be interesting to know if the ZR012 movement runs any smoother, requires extra lubricant and if it has a more consistent power delivery than a typical high-end Swiss mechanical movement – or is the rotary inspiration mostly aesthetic?

“C3H5N3O9 is a horological experiment carried out by MB&F partners, Maximilian Büsser, Serge Kriknoff and URWERK founders, Felix Baumgartner and Martin Frei. The aim is to work together (and with other partners) to create interesting timepieces that they could not do under their existing brands. C3H5N3O9 is an experimental platform, not a luxury brand.

At first glance the time appears to be indicated by centrally rotating triangular rotors; however, the triangles are actually Releaux polygons; they rotate eccentrically rather than centrally and track complex epitrochoid curves rather than circles. The system was inspired by the Wankel engine, which features orbital Releaux polygon rotors rather than the reciprocating pistons that power the majority of our cars and machines today.”

The Experiment ZRO12 indicates hours (by lower rotor along the front of the dial) and minutes (by a smaller upper rotor) with two Wankel engine eccentric rotating Releaux polygons (triangular-shaped rotors).

The ZR012 is powered by a manually wound mechanical movement with Releaux polygon (triangular-shaped) rotors, which are eccentric, meaning they are not mounted directly to the central crankshaft. “At these minuscule dimensions, the thickness of one tooth on the gears is not fine enough to precisely align the hour and minute wankels – normally you adjust by a complete tooth.

To ensure extremely high precision adjustment, the fixed wheels can be rotated slightly (then re-fixed) to allow fine adjustment and synchronized precision between the hour and minute indicators.” (180 plots to create epitrochoids for hours and minutes. Maximum tolerances of 0.20 mm between the hour and minute indication rotors and inside of epitrochoid.)

The movement has 42 jewels, 328 components and runs at a frequency of 28,800 vph. Power reserve 39-hours indicated on the case back. Satin finishing, sandblasting, circular graining, black PVD treated components and black ruthenium-treated components.

The Experiment ZR012 features a 60 component titanium case with zirconium lugs and measures 59mm long x 44mm wide x 17mm high. It has an articulated front lug, compound rear lug, which wraps ergonomically around the wrist making the timepiece fit more comfortably. Sapphire crystal with anti-reflective treatment both side.

Water-resistance 30 meters. Brown calf leather strap with titanium and white gold (palladium 150 alloy) folding buckle. The price is $114,000.

Jason Pitsch
Posted by:Jason Pitsch

Jason Pitsch is the Founder of Professional Watches. He appreciates good design and engineering in everything from architecture to automobiles to cameras to clothing. Yet his focus for the past decade has remained consistent on covering just one type of craftsmanship: watchmaking.